Philanthropist Brooke Astor hated her daughter-in-law so much that she told her doctor she would rather spend Christmas with her two dogs over “that bitch,” according to testimony today in Manhattan court.

At the ongoing trial of Astor’s son Anthony Marshall — accused of swindling $60 million from his mother’s estate by forcing her to amend her will while she suffered from senility — Astor’s ear doctor, Kevin O’Flaherty, said the elderly socialite truly disliked her son’s wife.

O’Flaherty took the stand in Manhattan Supreme Court and said that while he was treating Astor in 2000 inside her Park Avenue home, he asked her if she’d be spending Christmas with Marshall and his wife Charlene.

“She said she’d rather have Boysie and Girlsie, her dogs, there than her son and that…” he said, before spelling the word bitch.

Asked by prosecutors if Astor spelled the word or blurted it out, O’Flaherty said, “She said it.”

O’Flaherty, a prosecution witness, treated Astor from 1988 to 2007.

Marshall, 84, and his lawyer Francis Morrissey are charged with taking advantage of Astor’s poor mental condition to loot her will.

Astor died in 2007 at age 105.

The DA has argued that Charlene — formerly the wife of Astor’s minister in Maine — left her family and married Marshall.

Prosecutors have charged that Charlene was Marshall’s motivation for taking advantage of his mother’s money so that he could leave it to her upon his death.

When Marshall’s lawyer Ken Warner asked O’Flaherty if he asked her more questions about Astor’s holiday plans after she dropped the b-bomb, he said, “No, I just dropped it.”